Baffled mercury switch



Dec. 5, 1939. J. H. sTALEY BAFFLED MERCURY SWITCH Filed March 19, 1958 IPremsa Dsc. 5, 1939 UNITED' sTATss PATENT osrlcsf naman" rzrtzczzirswrrmry l* Joseph 1T.I Sisley. columbus, rnd. Application umn 19, 193s, sei-u1 No. 199,828

'This invention =relates to a mercury switch of the tubular, metal wall type, and reference is made to my United States Letters Patent No. 1,906,118 for a Mercury switch, issued April 25,

I'he primary object of this invention is to provide means within the tube forming the switch to prevent splashing of the mercury as it flows from one electrode tothe other or bridges therebetween, and further, to provide means for setting up a time delay in the making and breaking of a circuit by the switch through controlled iiow of the mercury.

These and other objects and advantages of the invention will become apparent to those versed in the art from the following description as illustrated in the accompanying drawing, in which Fig. 1 is a central longitudinal section through a structure embodying the invention;

Fig.'2, a transverse section o'n the line 2-2 in Fig. 1;

P18. 3, a similar view in section showing a modiiied form:

Fig. 4, a similar view in section of a further modified form;

Fig. 5, a similar view in section of a still further modified form;

Pig. 6, a detail in longitudinal section of that form. of the invention shown in Fig. 5 in further modined form;

Fig. 7, a longitudinal vertical section through a still further modiiled form; and v Fig. 8, a transverse section on a larger scale on the line 3 3 in Fig. 7. y

The switch is primarily built up to have a tubular metallic body Il having one end closed and the other end receiving thereover an insulating sleeve II over which isengaged a cap I2 in telescoping arrangement and forming a tight nt between the various members to effect va gas tight seal therebetween.

A refractory bushing I3, hereinafter termedv a breaker, is compressibly held within the insulating sleeve Il adjacent the cap end. The breaker I3 is made out of any suitable material which will resist deterioration under the action of an electric arc which may occur within the central bore through the breaker. This material may be varied but will take on the nature of soap-stone or fused silica mixtures.

The internal formation of the breaker I3 may vary somewhat in detail but it is necessary that there be a bore therethrough through which mercury I I may flow to form a connecting medium between thebody I0 and the cap I3 so as to establish an electric circuit therebetween as the body may be rocked accordingly. Also the internal shapeV of the breaker I3 must bermade to assist w in quenching the 'arc that may arise as .theY mer- (ol. zoo-ss) cury connection between the two electrodes is broken by reverse tilting of the switch.

In the present form, as is also shown in my patent above referred to, this `breaker I3 has an internal bore consisting nrst of a short cylindrical length I5 at the cap end and then an env larging bore extending rearwardly therefrom inY a conical manner as indicated in Fig. 1.

When the switch is .given a rather quick motion in tilting, the mercury Il may be thrown to the end of the chamber with the result that some of the mercury will rebound in thel nature of a splash and occasionally cause a re-establishment or a re-making of the electrical circuitbetween the body and cap parts of the switch. In inay`V installations, this action is extremely detrimental. In order to overcome this action, a diaphragm or baille I3 is introduced within the chamber of the switch to extend 'across the chamber to be in the path of the mercury I4 as it may iiow toward and away from the cap I2 through the bore II. 'I'his baille I8- may take a number of forms depending upon the nature of service requiredv for individual installation. l

In the form shown in Figs. 1 and 2, the baille I6 is` a disk of metal having a central bore I1 therethrough with va plurality of smaller holes I3 spaced therearound. This disk I3 is held in position by being placed across' the end of thel tube III within thesleeve II and there-held by pushing the breaker I3 snugly theeagainst. In this form the metal baille I6 becomes an extension oi the electrode body III. As the tube may be tilted, the mercury I4 may flow through the various holes I1-and I8 depending upon the degree of tilt of the tube and its axial rotated position. In any event, the mercury may iiow initially through the smaller holes I3 and more rapidly througl the larger hole I'I upon increased tilting of the tube,v but in any event,v

`the baille presents a retarding innuence upon the flow of the mercury to either side thereof.

It is obvious that by controlling the sizes of these holes, a suitable time delay may be secured in the iiow of the mercury from one side of the baille to the other in order to .convey all of the volume of the mercury through the baile.

In some instances, the flow of mercury will be better controlled by omitting the central hole I'I and merely employing a series of holes Il, Fig. 3, spaced around the baille at-regular intervals.

A still further modification of the baille means isshown in Fig. 4 where the baille 20 is made to have a diameter less than that .of 'the internal diameter of the chamber in the tube I0 and legs 2i, here shown as four (4) lin number, are provided to extend from the baille to be engaged between the ends of the bodyl I3 and the 'breaker I3. This construction provides a baille blocking of! the central area of thechamber and leaving o0.

arcuate openings y22, around the edge of the baille immediately vadjacent the wall of the chamber and within'the tube. A further obstruction or retarding influence is offered by lreason of the fact that a groove is left in the chamber between the legs 2l and the ends of the body it and the breaker i3.

`T he form of the baille 20, as shown in Fig. 1i, may be further modified to have a central hole 23 therethrough as indicated in Fig. 5 so as to permit a freer iiow of the mercury past the baiie.

As indicated in Fig. 6, the bade i2@ in either or both forms may be spaced away from the end ci the breaker i3 back into the chamber of. the body I if desired, particularly to secure greater area of contact between mercury and the tubewall, by providing longer legs 2i and bending them forwardly and then around into the groove between the body and breaker ends. It is obvious that when thebaiiie in any of the forms indicated is made of metal, the baille then serves, as above indicated, as a part of the electrode formed by the body i0. However, it is possible and desirous in some instances to make this baiie of a non-conducting material to have it in effect as a part of the breaker liti rather than as a part of the body lb.

As indicated in Fig. i, a baffle Q5 (taking the form of any of the other bales described), may be mounted directly in the chamber of the body i0 by forcing the baule therein with a pressed rit. This structure permits the bafe to be spaced much further back of, the breaker i3 and is permitted by the extended legs di in the form shown in Fig. 6. Under some conditions both baiiies iii `and 25 would beemployed in the same switch for greater time delay.

Referring to Figs. 7 and ii, avery effective anti-splash means is employed in the nature of anf iron ball 2E which merely floats on the mercury and is of sumcient diameter as will prevent splash back past it' ofthe mercury. The ball should be at least substantially equal in diameter to two-thirds of the chamber diameter in the body lli. In order to prevent stoppage of the bore through the breaker i3, some ball intercepting means is provided to stop the bali but permit the merucry to flow on past to the breaker. This intercepting means may take a number of forms such as pins or the like projecting from .the wall of the body chamber, or any transversely extending member, the form herein shown, Fig. 8, comprising a pair of crossed pins or wires 21 formed integrally and held against longitudinal displacement. In any event, the ball 26 serves very effectively as a baiiie.

While I have herein shown and described my invention in the particular forms, it is obvious that further structural variations may be employed without departing from the spirit of the invention, and I, therefore, do not desire to be limited to such precise forms beyond the limitations as may be imposed by the following claims.

I claim:

1. In a mercury tube switch, a metal tube serving as an electrode, a quantity of mercury owable in the tube, an electrode carried by and insulated from said tube, a breaker between the electrode and the tube, and a-mercury flow baffle maintained in abutment with the. tube by said breaker.V

2. In a mercury tube switch, a metal tube serving as an electrode, a quantity of mercury owable in the tube, an electrode carried by and insulated from said tube, a breaker between the electrode and the tube, and a mercury ow batiie between the breaker and the tube, said baille having a major central mercury iiow passage therethrough, and a plurality of additional passages smaller in size from said one passage concentrically positioned therearound whereby said mercury may quickly flow through the bale upon tilting of the tube to cause the mercury to reach the level of and pour through said major passage and comparatively slowly ow through the baille through said smaller passages only upon less tilting of the tube.

.3. In a mercury tube switch, a metal tube serving as an electrode, a quantity of mercury owable in the tube, an electrode carried by but insulated from said tube, a breaker between the electrode and the tube, and a mercury iow baille between the breaker andthe tube, and mounting legs extending from the baiiie compressively 2.0

gripped between said breaker and said tube.

4. In a mercury tube switch, a metal tube serving as an electrode, a quantity of mercury iiowable in the tube, an electrode carried by but insulated from said tube, a breaker between the electrode and the tube, and a mercury ilow baille between the breaker and the tube, a shoulder around the tube, said baiile being mounted against said shoulder, and said breaker compressively yretaining the baiile against the shoulder.

- around between said legs.

6. In a mercury tube switch having a chamber therein, a pair of electrodes in spaced apart relation in the chamber, a quantity of mercury flow- ;able in the chamber upon tilting thereof to bridge the electrodes, ,and a baiile in said chamber between the electrodes having a major central opening surrounded by a plurality of lesser openings, whereby a quick iiow of mercury is had through the baille upon tilting the switch to have the mercury pass through the major opening and a slower iow is had-upon less tilting to conne the flow through said lesser openings.

7. In a mercury tube switch, 'a metal tube serving as an electrode, a quantity of mercury flowable in the tube, an electrode carried by and insulated from said tube, a-breaker between the electrode and the tube, and a mercury ilow baille maintained in abutment with the tube by said breaker, said electrode consisting of a, tubular member telescoping with'said tube, an insulating electrode and the tube, and a mercury flow baille maintained in abutment with the tube by said,

breaker, said tube having an extension beyond said baille abutment, and said breaker being carried in said extension in compressive engagement with said baffle. I

JOSEPH H. STALEY. 

